Author: Murphy, J.M.
Paper Title Page
TUC3O07 Safety Integrity Level (SIL) Verification for SLAC Radiation Safety Systems 1
 
  • F. Tao, E. Carrone, J.M. Murphy, K.T. Turner
    SLAC, Menlo Park, California, USA
 
  SIL is a key concept in functional safety standards: it is a performance measure on how reliable is a safety system performing a particular safety function. In the system design stage, SIL verification must be performed to prove that the SIL achieved meets/exceeds the SIL assigned during risk assessment, to comply with standards. Unlike industrial applications, where safety systems are usually composed of certified devices or devices with long usage history, safety systems in large physics laboratories are less standardized and more complex in terms of system architecture and devices used. In addition, custom designed electronics are often employed, with limited reliability information. Verifying SIL for these systems requires in-depth knowledge of reliability evaluation. In this paper, it is demonstrated how to determine SIL using SLAC radiation safety systems (Personnel Protection System (PPS) and Beam Containment System (BCS)) as examples. PPS utilizes commercial safety rated devices, while BCS also contains customized electronics. Choice of standards, methods of evaluation, reliability data gathering process (both from industry and from hardware development) are also discussed.  
slides icon Slides TUC3O07 [1.754 MB]